In recent years, a diagnostic method is known which includes inserting an endoscope into a human body with an optical probe introduced through the endoscope, irradiating thereafter a site to be diagnosed inside the body with excitation light via this optical probe, measuring fluorescence generated by the excitation light and inspecting and/or analyzing the site to be diagnosed. Since the optical probe is inserted into the human body in this diagnostic method, it is desirable to replace the optical probe with a new one every time it is used. Therefore, there is a demand for a further cost reduction of the optical probe.
The optical probe is constructed of an optical connector plug to be connected to an optical apparatus, an optical cable composed of a plurality of optical fibers inserted into a tube to emit excitation light and illumination light and capture fluorescence from a distal end, and the like.
Furthermore, as a prior art related to the present invention, PTL 1 discloses an optical connector plug capable of connecting a plurality of optical routes at a time.